Apparatus for forming or dressing grinding wheels for use in formgrinding operations



April 1941- .J. E, VVAINWRIGHT 2.237.976

APPARATUS FOR FURMING OR DRESSING GRINDING WHEELS FOR USE 1NFORM-GRINDING OPERATIONS Filed July 11, 1940 gm 2mm? Ma m 046mmffiaico-ui Glimmg Patented Apr. 8, 1941 UNITED STATES PATENT OFFICEAPPARATUS FOR FORMING OR DRESSING GRINDING WHEELS FOR USE IN FORM-GRINDING OPERATIONS Application July 11, 1940, Serial No. 344,991 InGreat Britain November 8, 1938 3 Claims.

This invention relates to apparatus for forming or dressing grindingwheels for use in form-grinding operations in which the form is of aspecial kind, such for example, as is required in hobs for machiningsplines by a generating motion. In this method of producing splines itis necessary for the teeth of the hob to have such a curve as willgenerate plane surfaces at the sides of the splines parallel with eachother and with a radial plane passing through the centre of the spline.This curve is one of irregular progression and is at present obtained bytrial and error from a former-controlled hob-grinding wheel.

In my co-pending application Serial No. 344,- 992, filed July 11, 1940,a method is described for forming or dressing grinding wheels for use inthe production of formers from which to produce hobgrinding wheels tothe correct curvature for the purposes above described.

The object of the present invention is to provide improved apparatus forforming or dressing the operative surface of hob-grinding wheels bymeans of formers.

According to this invention former-controlled apparatus for the purposesherein referred to comprises a slide having a rectilinear motion withrespect to the former and carrying a pair of rigidly connected springarms, one of which carries a stylus cooperating with the former whilstthe other arm carries a dressing tool for producing the required form onthe hob-grinding wheel. In this way the movement of the stylus along thecontour of the former is accurately reproduced at the dressing tool in avery simple manner.

In order that the invention may be clearly understood and readilycarried into practical effect, reference is made in describing the sameto the accompanying drawing, in which 2 represents the former and 3 thehob-grinding wheel.

The apparatus employed according to this invention for reproducing thecontour of the former at the operative surface of the grinding wheelcomprises a slide 4 having a rectilinear motion with respect to theformer 2 and carrying a pair of parallel spring arms 5, 6 connectedtogether by means of a rigid yoke I one limb of which carries a stylus 8adapted for co-operation with the former 2, whilst the other limbcarries a dressing tool 9 for forming the operative surface of thehob-grinding wheel 3. The slide 4 is mounted in a relatively stationaryguide plate 4* to which the former 2 may be conveniently fixed. Anysuitable means may be employed for reciprocating the slide in the guiderelatively to the former 2.

I claim:

1. Apparatus for the purposes herein described comprising a stationaryformer and a slide having a rectilinear motion relatively thereto andcarrying a pair of rigidly connected spring arms, a stylus fixed to oneof said arms and adapted to co-operate with said former and a dressingtool carried by the other of said arms and adapted for forming theoperative surface of a hob-grinding wheel.

2. Apparatus for the purposes herein described, comprising a stationaryguide plate, a slide mounted therein, a former fixed to said guideplate, means for reciprocating said slide in said guide relatively tosaid former, a pair of rigidly connected spring arms carried by saidslide, a stylus carried by one of said arms and adapted to have slidingcontact with said former, and a dressing too-1 carried by the other ofsaid arms and adapted for forming the operative surface of ahob-grinding wheel.

3. Apparatus for forming or dressing grinding wheels comprising a slide,a, pair of relatively spaced parallel spring arms fixedly attached at Itheir corresponding stationary ends to said slide,

a stylus mounted adjacent the free end of one of said arms for movementtherewith, a dressing tool mounted adjacent the free endof the other ofsaid arms for movement therewith, and means extending between andrigidly connecting thefree end portions of said arms to producesimultaneous equal movement of said stylus and dressing tool.

J OHN ERNEST WAINWRIGHT.

